From Short-Bite Ligand Assembled Ribbons to Nanosized Networks in Cu(I) Coordination Polymers Built Upon Bis(benzylthio)alkanes (BzS(CH₂)_nSBz; n = 1–9)

Abstract

With the objective to establish a correlation between the spacer distance and halide dependence on the structural features of coordination polymers (CPs) assembled by the reaction between CuX salts (X = Cl, Br, I) and dithioether ligands BzS(CH 2 ) n SBz (n = 1−9; Bz = benzyl), a series of 26 compounds have been prepared and structurally investigated. A particular attention has been devoted to the design of networks with extremely long and flexible methylene spacer units between the SBz donor sites. Under identical conditions, CuI and CuBr react with BzSCH 2 Bz (L1) affording respectively the one-dimensional (1D) CPs {Cu(μ 2 -I) 2 Cu}(μ-L1) 2 ] n (CP1) and {Cu(μ 2 -Br) 2 Cu}(μ-L1) 2 ] (CP2), which incorporate Cu(μ 2 -X) 2 Cu rhomboids as secondary building units (SBUs). The hitherto unknown architecture of two-dimensional (2D) layers obtained with CuCl (CP3) differs from that of CP1 and CP2, which bear inorganic −Cl−Cu−Cl−Cu−Cl− chains interconnected through bridging L1 ligands, thus forming a 2D architecture. The crystallographic characterization of a 1D CP obtained by reacting CuI with 1,3-bis(benzylthio)propane (L2) reveals that [{Cu(μ 2 -I) 2 Cu}(μ-L2) 2 ] n (CP4) contains conventional Cu 2 I 2 rhomboids as SBUs. In contrast, unusual isostructural CPs [{Cu(μ 2 -X)}(μ 2 -L2)] n (CP5) and (CP6) are obtained with CuX when X = Br and Cl, respectively, in which the isolated Cu atoms are bridged by a single μ 2 -Br or μ 2 -Cl ion giving rise to infinite [Cu(μ 2 -X)Cu] n ribbons. The crystal structure of the strongly luminescent three-dimensional (3D) polymer [{Cu 4 (μ 3 -I) 3 (μ 4 -I)(μ-L3) 1.5 ] n (CP7) issued from reacting 2 equiv of CuI with BzS(CH 2 ) 4 SBz (L3) has been redetermined. CP7 features unusual [(Cu 4 I 3 )(μ 4 -I)] n arrays securing the 3D connectivity. In contrast, mixing CuI with an excess of L3 provides the nonemissive material [{Cu(μ 2 -I) 2 Cu}(μ-L3) 2 ] n (CP8). Treatment of CuBr and CuCl with L3 leads to [{Cu(μ 2 -Br) 2 Cu}(μ-L3) 2 ] n (CP9) and the 0D complex [{Cu(μ 2 -Cl) 2 Cu}(μ-L3) 2 ] (D1), respectively. The crystallographic particularity for CP9 is the coexistence of two topological isomers within the unit cell. The first one, CP9-1D, consists of simple 1D ribbons running along the a axis of the unit cell. The second topological isomer, CP9-2D, also consists of [Cu(μ 2 -Br) 2 Cu] SBUs, but these are interconnected in a 2D manner forming 2D sheets placed perpendicular to the 1D ribbons. Four 2D CPs, namely, [{Cu 4 (μ 3 -I) 4 }(μ-L4) 2 ] n (CP10), [{Cu(μ 2 -I) 2 Cu}(μ-L4) 2 ] n (CP11), [{Cu(μ 2 -Br) 2 Cu}(μ-L4) 2 ] n (CP12), and [{Cu(μ 2 -Cl) 2 Cu}(μ-L4) 2 ] n (CP13), stem from the self-assembly process of CuX with BzS(CH 2 ) 6 SBz (L4). A similar series of 2D materials comprising [{Cu 4 (μ 3 -I) 4 }(μ-L5) 2 ] n (CP14), [{Cu(μ 2 -I) 2 Cu}(μ-L5) 2 ] n (CP15), [{Cu(μ 2 -Br) 2 Cu}(μ-L5) 2 ] n (CP16), and [{Cu(μ 2 -Cl) 2 Cu}(μ-L5) 2 ] n (CP17) result from the coordination of BzS(CH 2 ) 7 SBz (L5) on CuX. Ligation of CuX with the long-chain ligand BzS(CH 2 ) 8 SBz (L6) allows for the X-ray cha...

A Fused Poly(truncated rhombic dodecahedron)-Containing 3D Coordination Polymer: A Multifunctional Material with Exceptional Properties

“…Both CP1 and CP2 are colorless solids (Figure S7), and their absorption bands are in the UV region of the spectra (λ < 350 nm; Figure , black lines). Again, the literature proves that Cu x I x S y SBUs exhibiting a globular geometry are always associated with an intense emission. − In addition, the emission band maxima (λ emi ) of cubane-containing species are usually located between ∼520 and 620 nm and exhibit emission lifetimes (τ emi ) ranging within the 0.8 < τ emi < 10 μs time scale, as either mono- or biphasic decays at 298 K (a recent literature survey of all globular shaped SBUs was performed; see Supporting Information of ref ) . Unsurprisingly, this is also the case for CP1 (Table ).…”

“…The former category, which includes hexagonal prism − and fused dicubane, − is systematically strongly luminescent, whereas the rhomboid motif is mostly either weakly emissive or non-emissive (but not exclusively as rare examples exist) . On many occasions, the facile control of the SBU structure, globular vs quasi-planar , mainly cubane Cu 4 I 4 L 4 vs rhomboid Cu 2 I 2 L 4 , has been performed by simply adjusting the stoichiometric ratio Cu atom/S atom, thus controlling the luminescence properties ( on or off ). ,, Generally, the SBU geometry consists of a distinct cluster, but on rare occasions, the SBU motif exhibits a polymeric 1D-[CuI] n skeleton (Figure ). These 1D-[CuI] n motifs are accordion ribbon, , zigzag ribbon, staircase ribbon, and polycubane, , and again, these quasi-planar SBUs are either weakly emissive or non-emissive (accordion, zigzag, and staircase ribbons).…”

“…Concurrently, the globular polycubane SBU exhibits an intense emission. The band maxima (375 < λ emi < 540 nm) and emission lifetimes (1 < τ emi < 15 μs) have been evaluated for a few of these 1D-SBU-containing materials, − and the 1D polycubane exhibits the most red-shifted band and longest lifetimes.…”

“…Structures of the 1D-[CuI] n SBUs encountered in neutral mono- and dithioether/CuI-containing CPs (S = sulfur atom of the thioether ligand). − …”

Crystal structures of 9-[bis(benzylsulfanyl)methyl]anthracene and of cyclo-dodecakis(μ2-phenylmethanethiolato-κ2 S:S)hexapalladium(6 Pd—Pd)–anthracene-9,10-dione (1/1)

“…Over the last few years, we have been engaged in exploring the assembly of molecular cluster compounds and coordination polymers using thioether ligands RSCH 2 SR (Peindy et al, 2007;Knorr et al, 2014;Schlachter et al, 2020). Recently, we have also reported the synthesis of Cu I coordination complexes ligated with cyclic thioacetal ligands bearing various substituents (Raghuvanshi et al, 2017(Raghuvanshi et al, , 2019Schlachter et al, 2018;Knauer et al, 2020).…”